


Knot Expected

by Unforth



Series: Prompt Fics: Supernatural [93]
Category: Supernatural
Genre: Alternate Universe - Modern Setting, Aphrodisiacs, Bottom Castiel (Supernatural), Butt Plugs, Cock Rings, Dog Castiel (Supernatural), Dog Dean Winchester, Feminizing Language, Guilty Pleasures, Knotting, M/M, Mild breeding kink, Pet Play, Plot What Plot/Porn Without Plot, Roughhousing, Subspace, Top Dean Winchester, pet roleplay
Language: English
Status: Completed
Published: 2021-01-31
Updated: 2021-01-31
Packaged: 2021-03-18 03:41:02
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,802
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29111724
Author URL: https://archiveofourown.org/users/Unforth/pseuds/Unforth
Summary: Cas wants to use their rope ball to play "tug of war" with Dean...Dean has other ideas...
Relationships: Castiel/Dean Winchester
Series: Prompt Fics: Supernatural [93]
Series URL: https://archiveofourown.org/series/708447
Comments: 21
Kudos: 100





	Knot Expected

**Author's Note:**

  * For [hullosweetpea](https://archiveofourown.org/users/hullosweetpea/gifts).



> Note that this is NOT BDSM petplay so much as roleplaying petplay - they're both pets, neither one is playing the "owner" role. 
> 
> Second note: the term alpha is used but this is NOT A/B/O.
> 
> Third note, I can't seem to focus well enough to edit, I'm sorry. I hope it's not a mess...

Trembling, Castiel forced himself to take deep breaths and let his tongue loll out. The first few minutes after he donned his paws and knee pads and snout and ears and tail were always harrowing; he felt a fool scrambling over the floor, sniffing at the couch, lapping at water from a bowl. Only the knowledge that the feeling would fade kept a panicky sense that he was doing something  _ wrong  _ at bay. 

Deep breath.

_ Oh, look, a ball… _

Slow exhale.

Padding over, Castiel...no, Cas, always Cas when he was a pup...nudged the rope-ball with his nose; it rolled toward the TV stand.

Deep breath.

_...that’s kinda fun… _

Slow exhale.

Cas scrambled after the ball, grabbed rope with his teeth, and tossed it in the air. It conked him in the face and he laughed, a snuffling, in human sound, as he grabbed it again and thrashed it around. Oh, but he loved shamelessly, innocently  _ enjoying  _ something. The rope was abrasive against his tongue - another thing he loved. He tossed it across the room, romped after it, grabbed it again, threw it again, chased it, and--

A growl arrested Cas and he stopped a few steps shy from the ball and padded back. Another dog - Dean, gorgeous in his furry perked-up ears and silken tail - stalked to stand over the ball, baring teeth at Cas. Confused, Cas settled on his back haunches and tilted his head to one side. If Dean wanted to play with him, all he had to do was initiate, and instead...Dean dropped down, ass up, elbows on the floor, rope ball between his forearms, in a clear challenge. His scent was off, too - muskier than usual, alluring, heady and dizzying.

Swallowing a whimper, Cas shivered as a tingle ran down his spine. They’d talked about this - suggested they might do it  _ someday _ , but Dean hadn’t suggested that  _ someday  _ was  _ now _ , the last time it came up.

_ But I don’t want to think about that...I don’t want to think...I just want… _

_...everything that scent promises, everything we talked about, everything we… _

_...no! _

_ I just want the ball. _

_ That’s my ball! _

With a snarl, Cas leapt forward, head extended to grab the rope loop, but Dean grabbed it and pulled it backwards. Unbalanced, Cas tumbled forward, and Dean leapt at him. Paws clashed with paws, snouts knocked at snouts, as they rolled and fought. Dean’s teeth caught at Cas’ side, tearing without breaking skin. Cas’ claws raked over Dean’s chest and belly. They’d never fought before - usually Cas far preferred to play with their toys, exchange butt sniffs, maybe curl up together in a patch of sunshine and bask - but Dean clearly wanted to assert dominance, and there was no way Cas would go down without a fight. His head slammed the floor as Dean knocked into him; rolling, he got his paws under him and rounded savagely, nipping and growling. Dean gave as good as he got, rearing up on his hind legs, intent on driving Cas to floor, but Cas instead rose to meet him. Their front paws locked and they both struggled to knock the other over, to keep their balance, to  _ win _ . Paired erections thrust into that still air, Dean’s fat around the base where something unfamiliar thickened him, demonstrating their arousal, and only time would tell which of them would own, and which would be owned. Cas’ muscles trembled with effort, and his insides trembled with delight.

_ Soon _ .

Dean was so  _ strong _ .

_...oh, oh, I want...I need...is he really going to...am  _ I  _ really going to... _

It was so  _ incredible _ .

_...but is he really worthy? If he really wants...if he wants me as badly as I want him, he’s gonna have to earn me… _

Dean surged forward, teeth gnashing air inches from Cas’ face, and Cas’ arms gave way abruptly. Yelping, he tumbled backward, twisting to try to keep his legs under him. Dean’s paws landed heavily on his hips, nearly pinning him, but Cas wasn’t down yet. He scrambled forward, seeking the couch and the high ground it would afford him if he could get atop it. Behind him, Dean’s claws click-clacked over the hardwood floor as he raced to catch up. Bunching himself, Cas leapt--

\--and paws seized his midsection, arresting him mid-jump. Front paws and chin slamming into the front couch support, Cas tried to fight through being momentarily stunned to escape, but Dean was irresistible, powerful, snuffling and nipping at Cas’ back, sliding himself up, up, up Cas’ body. With every shift, Dean’s hips thrust, knocking Cas’ tail aside. The lubricated plug part tingled sensation up Cas’ spine, and though Cas still fought for freedom, his willpower was fading. As their bodies grew closer, every one of Dean’s movements knocked thick cock against Cas’ backside. Cas’ breathing, heavy with effort, grew strained, each exhale tinged with a needy mewl. Dean’s growls were raspy and feral; he slammed his hips forward - and slid over lubricant - slammed forward - and knocked into Cas’ balls - slammed forward, forward, forward, glancing off Cas’ backside as he sought entry. Cas’ struggles subsided.

He recognized the smell of aphrodisiac - the smell of a mutt in heat.

He recognized that Dean  _ did  _ want to play, and  _ had  _ brought a toy, it just wasn’t a ball.

He recognized they--

Dean’s cock slammed into his body and Cas  _ howled _ . Oh, but he was so full, and Dean was so big - even bigger than usual,  _ fuck _ , there was something on his dick, fattening it, and Cas wanted,  _ needed _ , whatever it was. Having found purchase and entrance, Dean picked up a hard, fast pace, thrusting unrelentingly into Cas’ bodies. Dean had proven his dominance, and Cas was  _ elated  _ to have the pack alpha seize what he wanted from Cas’ body. Whines and gasps marked the waves of pleasure that surged through Cas with every thrust. Fur tickled at his back where Dean licked and lapped at him with his muzzle. Claws dug into Cas’ belly where Dean’s front paws grabbed him and pulled him back, hard, into every thrust. On and on, they went, Dean using him mercilessly, Cas’ cock slapping his belly over and over, the room whiting out, the air suffused with the smell of sex. 

Dean had always been hung.

But the catch at Cas’ rim as Dean fucked him and fucked him...that was new.

Dean was getting  _ bigger _ .

And Cas could swear he’d never felt better in his life. Snarling, Dean’s thrust grew more aggressive as whatever he’d been wearing at the base of his cock expanded, almost like…

... _ like a knot, oh, he’s got a knot, this is… _

Cas couldn’t say any longer if he was yelping or sobbing - couldn’t say any longer if he was a human or a dog. All he knew was that he was  _ Dean’s _ , to use and take and breed, and he’d never wanted anything more. Dean’s chest heaved against Cas’ back with the effort of his vigorous fucking, his hips snapping forward, forward, forward, to punch the growing bulge into Cas’ body. Arms giving way, Cas crumpled against the couch cushions, snout digging into his cheeks, lips working around words he barely repressed.

Thrust.

_ Knot me, Dean! _

Thrust.

_ Fuck me, alpha! _

Thrust.

_ Claim me, pack leader! _

Thrust.

_ Wanna be your good bitch! _

Thrust.

_ Wanna go into heat for you. _

Thrust.

_ Wanna-- _

Dean pulled back...and couldn’t. Cas’ rim _screamed_ pain with the strain of trying to take something big into his body and, once it was in him, couldn’t stretch far enough to allow Dean to withdraw at all. 

“Fuck...oh, fuck…” Dean sobbed against Cas’ back, and Cas’ was past caring that words had been used - wasn’t sure he hadn’t broken the rule first. His entire body was afire, and he couldn’t think, couldn’t roleplay, couldn’t maintain the illusion - he could only feel, and oh, he felt...

“Dean!” he gasped.

...he felt...

“Know...fuck, I know...it’s so much...too much…take it, bitch...take it, take it…take me...”

...felt…

Desperate, unable to withdraw, Dean humped forward, slamming into Cas’ body over and over again, so hard that the couch knocked into the wall behind it. 

...he felt  _ incredible. _

There was no reaching for his own cock, no stroking himself, but it didn’t matter. He  _ was  _ Dean’s bitch, Dean’s  _ good  _ bitch, and it was enough that his alpha was using him, enough that--

Teeth sank into Cas’ shoulder, surging pain through him. Claws raked down Cas’ chest. Dean’s hips slammed forward one more time and then Dean threw his head back, tearing away from Cas’ tortured arm, and howled through his climax.  _ Fuck _ , but Cas could  _ feel  _ Dean spilling into him, more copiously than should be possible. Dizzy, swooning, he was held up by solely by the couch before him and Dean behind him and Dean’s cock within him.

He was  _ so close _ .

But he wasn’t  _ there _ .

Desperate, he rocked back. Dean choked, and more come splashed Cas’ insides. 

So close.

Again, Cas fucked himself back - so close - and again - so close - and again - so close - seizing what he needed as Dean sobbed and switched and whined his over-stimulation. The knot pulled gloriously at Cas’ rim, and Dean’s front paws scrambled at Cas’ chest. Maybe they’d used words by accident, but it didn’t matter - Cas was his alpha’s toy, and that cock was  _ Cas’  _ toy, and he would come, he would, he would, he--

“Good dog.”

And, with a howl, Cas came, untouched, cock spitting semen to dribble down the side of the couch. 

...and there was stillness, save for Dean’s torso trembling against Cas’ back…

...and there was silence, save for their heavy breathing…

...and there was the lingering scent of musky aphrodisiac…

...and there was Dean’s cock throbbing inside Cas…

...and there were Cas’ insides, roiled by bliss…

...and “That was incredible,” Cas mumbled.

“Sorry ‘bout the talking,” Dean replied, hoarse. “Didn’t mean to...couldn’t help...so fuckin’ hot, Cas…”

“S’ok,” said Castiel, and was pleased to realize he really meant it. Usually, he hated breaking roleplay because remembering he was a person flooded him with guilt, but now, with Dean inside him and around him, with a knot swelling his ass, Castiel searched himself for shame...and found none.

He  _ adored  _ what Dean had just done for him.

“Really?” Dean breathed hopefully.

Dean clearly adored it as well.

“Truly,” Cas confirmed. “Want to be your good bitch forever, Dean.”

Cas’ clenched his ass in emphasis, and Dean groaned.

“But, one suggestion?”

“Anything,” said Dean, fervent and loving and tender and dedicated and perfect.

“Next time,  _ I’m  _ taking the aphrodisiac…”

Dean groaned again, and Cas felt…

...happy, sated, content, used, stretched…

...Cas felt _wonderful_ …

...Cas felt like a good dog, and it was the best feeling in the world.

**Author's Note:**

> Yes I invented a sex toy just for this fic.
> 
> No, I'm not sorry.
> 
> Check me out on social media!  
> Tumblr: [unforth](https://unforth.tumblr.com/) (very multifandom with a decent amount of politics/social justice)  
> Twitter: [unforth](https://twitter.com/unforth) (mostly MDZS/CQL, with a splash of multifandom and also a decent amount of politics/social justice, cause sorry, them's the times)  
> Discord: unforth#6748


End file.
